Kaliningrad — the Russian exclave wedged between Poland and Lithuania, historically Königsberg — has no legal authority to issue currency, making these "marka" pieces private fantasy issues rather than sanctioned coinage. The X# prefix in Krause confirms this: World Coin's X-number series catalogs exonumia, tokens, and unofficial local issues entirely outside national monetary systems. The K-50 helicopter designation references the Kamov Ka-50 "Black Shark," a Soviet-developed single-seat attack helicopter that entered limited Russian service in the 1990s after a notoriously protracted development.
Kaliningrad — the Russian exclave wedged between Poland and Lithuania, historically Königsberg — has no legal authority to issue currency, making these "marka" pieces private fantasy issues rather than sanctioned coinage. The X# prefix in Krause confirms this: World Coin's X-number series catalogs exonumia, tokens, and unofficial local issues entirely outside national monetary systems. The K-50 helicopter designation references the Kamov Ka-50 "Black Shark," a Soviet-developed single-seat attack helicopter that entered limited Russian service in the 1990s after a notoriously protracted development.